I'm working on a Django project and encountering an issue with Django views. Here's my current implementation:

# models.py
# views.py
from django.shortcuts import render
from .models import Article

def article_list(request):
    articles = Article.objects.all()
    for article in articles:
        print(article.author.username)  # N+1 problem here
    return render(request, 'articles.html', {'articles': articles})

The specific error I'm getting is: "django.urls.exceptions.NoReverseMatch: Reverse for 'article_detail' not found"

I've already tried the following approaches:

• Checked Django documentation and Stack Overflow
• Verified my database schema and migrations
• Added debugging prints to trace the issue
• Tested with different data inputs

Environment details:

• Django version: 5.0.1
• Python version: 3.11.0
• Database: PostgreSQL 15
• Operating system: Ubuntu 22.04

Has anyone encountered this before? Any guidance would be greatly appreciated!

Python decorators with arguments require a three-level nested function. Here's the proper implementation:

import functools

# Decorator with arguments
def retry(max_attempts=3, delay=1):
    def decorator(func):
        @functools.wraps(func)  # Preserves function metadata
        def wrapper(*args, **kwargs):
            for attempt in range(max_attempts):
                try:
                    return func(*args, **kwargs)
                except Exception as e:
                    if attempt == max_attempts - 1:
                        raise e
                    time.sleep(delay)
        return wrapper
    return decorator

# Usage
@retry(max_attempts=5, delay=2)
def unreliable_function():
    # Function that might fail
    pass

Class-based decorator (alternative approach):

class Retry:
    def __init__(self, max_attempts=3, delay=1):
        self.max_attempts = max_attempts
        self.delay = delay
    
    def __call__(self, func):
        @functools.wraps(func)
        def wrapper(*args, **kwargs):
            for attempt in range(self.max_attempts):
                try:
                    return func(*args, **kwargs)
                except Exception as e:
                    if attempt == self.max_attempts - 1:
                        raise e
                    time.sleep(self.delay)
        return wrapper

# Usage
@Retry(max_attempts=5, delay=2)
def another_function():
    pass

The RecursionError occurs when Python's recursion limit is exceeded. Here are several solutions:

1. Increase recursion limit (temporary fix):

import sys
sys.setrecursionlimit(10000)  # Default is usually 1000

2. Convert to iterative approach (recommended):

# Recursive (problematic for large inputs)
def factorial_recursive(n):
    if n <= 1:
        return 1
    return n * factorial_recursive(n - 1)

# Iterative (better)
def factorial_iterative(n):
    result = 1
    for i in range(2, n + 1):
        result *= i
    return result

3. Use memoization for recursive algorithms:

from functools import lru_cache

@lru_cache(maxsize=None)
def fibonacci(n):
    if n < 2:
        return n
    return fibonacci(n-1) + fibonacci(n-2)

4. Tail recursion optimization (manual):

def factorial_tail_recursive(n, accumulator=1):
    if n <= 1:
        return accumulator
    return factorial_tail_recursive(n - 1, n * accumulator)

To handle Django database transactions properly and avoid data inconsistency, use Django's transaction management:

from django.db import transaction

# Method 1: Decorator
@transaction.atomic
def transfer_money(from_account, to_account, amount):
    from_account.balance -= amount
    from_account.save()
    
    to_account.balance += amount
    to_account.save()

# Method 2: Context manager
def complex_operation():
    with transaction.atomic():
        # All operations in this block are atomic
        user = User.objects.create(username='test')
        profile = UserProfile.objects.create(user=user)
        # If any operation fails, all are rolled back

For more complex scenarios with savepoints:

def nested_transactions():
    with transaction.atomic():
        # Outer transaction
        user = User.objects.create(username='test')
        
        try:
            with transaction.atomic():
                # Inner transaction (savepoint)
                risky_operation()
        except Exception:
            # Inner transaction rolled back, outer continues
            handle_error()

The RecursionError occurs when Python's recursion limit is exceeded. Here are several solutions:

1. Increase recursion limit (temporary fix):

import sys
sys.setrecursionlimit(10000)  # Default is usually 1000

2. Convert to iterative approach (recommended):

# Recursive (problematic for large inputs)
def factorial_recursive(n):
    if n <= 1:
        return 1
    return n * factorial_recursive(n - 1)

# Iterative (better)
def factorial_iterative(n):
    result = 1
    for i in range(2, n + 1):
        result *= i
    return result

3. Use memoization for recursive algorithms:

from functools import lru_cache

@lru_cache(maxsize=None)
def fibonacci(n):
    if n < 2:
        return n
    return fibonacci(n-1) + fibonacci(n-2)

4. Tail recursion optimization (manual):

def factorial_tail_recursive(n, accumulator=1):
    if n <= 1:
        return accumulator
    return factorial_tail_recursive(n - 1, n * accumulator)